TM4 of the glutamate transporter GLT-1 experiences substrate-induced motion during the transport cycle.

ABSTRACT: Excitatory amino acid transporter 2 (EAAT2), also known as glial glutamate transporter type 1 (GLT-1), plays an important role in maintaining the extracellular glutamate concentrations below neurotoxic levels. The highly conserved TM2 transmembrane domain of GLT-1 maintains a stable position during the transport cycle; however, the effect of the transport cycle on the topology of TM4 in not well established. To further reveal the function of TM4, two cysteine pairs between TM2 and TM4 were introduced using site-directed mutagenesis. A significant decrease of transport activity was observed in the I93C/V241C and I97C/V241C mutants upon application of the oxidative cross-linking reagent, copper (II) (1,10-phenanthroline)₃ (CuPh), which suggests that a conformational shift is essen

SUBMITTER: Rong X 

PROVIDER: S-EPMC5048300 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature